package string;

public class StringStringBuilderDemo {
    public static void main(String[] args) {
        StringBuilder stringBuilder=new StringBuilder("好好学习Java");
        stringBuilder.append(",就是为了找个好工作");
        System.out.println(stringBuilder);
        stringBuilder.replace(9,100,"就是为了改变世界");
        System.out.println(stringBuilder);
        stringBuilder.insert(0,"不");
        System.out.println(stringBuilder);
        stringBuilder.delete(0,1);
        System.out.println(stringBuilder);
        String s="a";
        StringBuilder bu1=new StringBuilder(s);
        for (int i=0;i<100000;i++){
            bu1.append(i);
        }
        }
    }

